Bump p-retry from 4.6.2 to 6.2.0 in /backend

Bumps [p-retry](https://github.com/sindresorhus/p-retry) from 4.6.2 to 6.2.0.
- [Release notes](https://github.com/sindresorhus/p-retry/releases)
- [Commits](sindresorhus/p-retry@v4.6.2...v6.2.0)

---
updated-dependencies:
- dependency-name: p-retry
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>